Method and apparatus for sorting

Abstract

A method and apparatus for sorting objects is described, and which provides high-speed image data acquisition to fuse multiple data streams in real-time, while avoiding destructive interference when individual sensors or detectors are utilized in providing data regarding features of a product to be inspected.

The invention claimed is: 
     
       1. A method for sorting a product comprising:
 providing a source of a product to be sorted; 
 transporting the source of product along a predetermined path of travel, and releasing the source of product into a product stream which moves in an unsupported gravity influenced free-fall trajectory; 
 providing an inspection station which is located along the trajectory of the product stream; 
 providing a first, selectively energizable illuminator, and locating the first illuminator on a first side of the product stream, and the inspection station, respectively; 
 providing a first, selectively operable image capturing device and locating the first image capturing device adjacent to the first illuminator; 
 energizing the first illuminator, and rendering the first image capturing device operable substantially simultaneously, for a first predetermined time period so as to illuminate the product stream moving through the inspection station, and generate an image signal with the first image capturing device of the illuminated product stream; 
 providing a second, selectively energizable illuminator, and locating the second illuminator on the first side of the product stream, and in spaced relation relative to the first illuminator; 
 providing a second, selectively operable image capturing device, and locating the second image capturing device adjacent to the second illuminator; 
 energizing the second illuminator so as to generate a narrow beam of light which is scanned along a path of travel which is transverse to the product stream moving through the inspection station, and further rendering the second image capturing device operable substantially simultaneously, for a second predetermined time period, which is subsequent to the first predetermined time period, and wherein the second illuminator illuminates with the narrow beam of light the product stream which is moving through the inspection station, and the second image capturing device generates an image signal of the illuminated product stream; 
 providing a third, selectively energizable illuminator which is positioned on a second side of the product stream, and which, when energized, illuminates the product stream moving through the inspection station; 
 providing a third, selectively operable image capturing device, and locating the third image capturing device adjacent to the third illuminator; 
 energizing the third illuminator, and rendering the third image capturing device simultaneously operable, for a third predetermined time period, so as to illuminate the product stream moving through the inspection station while simultaneously forming an image signal with the third image capturing device of the illuminated product stream, and wherein third predetermined time period is subsequent to the first and second predetermined time periods; 
 providing a fourth, selectively energizable illuminator, and locating the fourth illuminator on the second side of the product stream, and in spaced relation relative to the third illuminator; 
 providing a fourth, selectively operable image capturing device, and locating the fourth image capturing device adjacent to the fourth illuminator; 
 energizing the fourth illuminator so as to generate a narrow beam of light which is scanned along a path of travel which is transverse to the product stream moving through the inspection station, and further rendering the fourth image capturing device operable substantially simultaneously, for a fourth predetermined time period, which is phase delayed from, and partially overlapping with, the second predetermined time period, and wherein the fourth illuminator illuminates with the narrow beam of light the product stream which is moving through the inspection station, and the fourth image capturing device generates an image signal of the illuminated product stream; 
 providing a controller and coupling the controller in controlling relation relative to each of the first, second, third, and fourth illuminators, and image capturing devices, respectively; 
 providing and electrically coupling an image preprocessor with the controller; 
 supplying the image signals formed by the respective first, second, third, and fourth image capturing devices to the image preprocessor; 
 processing the image signals received by the preprocessor and the supplying the image signals to the controller to identify a defective product in the product stream passing through the inspection station, and wherein the controller generates a product ejection signal when a defective product is identified; and 
 providing a product ejector which is located downstream of the inspection station, and along the trajectory of the product stream, and wherein the controller supplies the product ejection signal to the product ejector to effect a removal of the identified defective product from the product stream.